Subterranean operations are commonly performed to retrieve hydrocarbons from different formations. A well may be drilled into a formation of interest and various operations may be performed to efficiently retrieve hydrocarbons from the subterranean formation. In many cases, a tubular string, such as a casing, a liner, a tubing or the like, is positioned within the wellbore. The tubular string increases the integrity of the wellbore and provides a path through which fluids from the formation may be produced to the surface. To produce fluids into the wellbore or tubular string, perforations may be made through the wellbore and/or tubular string and into the formation.
One method of creating these perforations is through the use of explosives, such as shaped charges. The shaped charges are usually disposed within a charge carrier of a perforating gun. The shaped charges typically include a charge case, a quantity of high explosive, and a liner. In operation, the perforations are made by detonating the high explosive which causes the liner to form a jet of particles and high pressure gas that is ejected from the shaped charge at very high velocity. This jet penetrates the wellbore or tubular string, thereby creating one or more openings extending from the wellbore or tubular string and into the formation. When the shaped charges are detonated, numerous metal fragments are created due to, among other things, the disintegration of the charge cases of the shaped charges. These fragments often fall out or are blown out of the holes created in the charge carrier. As such, these fragments become debris that may be left behind in the wellbore. This debris can obstruct production as well as the passage of tools through the wellbore or tubular string during subsequent operations. This is particularly problematic in long production zones that may be perforated in horizontal wells as the debris simply piles up on the lower side of such wells.
One approach to reducing the debris from the shaped charges is to make the shaped charges from a zinc alloy to reduce the amount of undesirable debris from the system. This is because zinc breaks up into very small particles upon detonation and may also change from a solid phase to a gas phase due to chemical reactions downhole. However, zinc charges also have their disadvantages. For example, the zinc detonation may result in an undesirably large and rapid pressure rise.
It is therefore desirable to design a shaped charge that can achieve the desired charge performance with reduced downhole problems. For instance, it is desirable to reduce debris fragmentation and substantially eliminate the rapid pressure rise often caused by prior art zinc charges.
While embodiments of this disclosure have been depicted and described and are defined by reference to exemplary embodiments of the disclosure, such references do not imply a limitation on the disclosure, and no such limitation is to be inferred. The subject matter disclosed is capable of considerable modification, alteration, and equivalents in form and function, as will occur to those skilled in the pertinent art and having the benefit of this disclosure. The depicted and described embodiments of this disclosure are examples only, and are not exhaustive of the scope of the disclosure.